Answers

Soak the seed overnight in warm water and a little washing up liquid. This removes the sticky coat which is normally licked off by ants. Then surface sow, they need light to germinate. If you must cover then use vermiculite, it lets light through. they do not need to be put in a bag or anything, just put the seed tray somewhere safe and let them get on with it. Sow thinly so you do not need to prick them out, they should be left until they go dormant again.
Must confess all I ever do is throw the seeds on the gravel garden and leave them to it.

Sorry. they will gorw a set of leaves which they keep until around the following June. When those leaves die down is the time to move them on. OR. If they are not crowded in the seed trays, then you can leave them for another season of growing. When I grew them in large numbers I used to just feed the seed trays with liquid food and pot them up when the corms were about an inch across.
All I was trying to say was that unlike some plants the babies do not like being moved until they have developed a goood root system and that takes about 12 months.